It is well known to use jaw clutches including clutch plates having opposing matingly engageable or interlocking teeth for connecting rotatable members such as a shaft and a sprocket or pulley for rotation of one by the other. Many such jaw clutches include at least one clutch spring for exerting a spring force against the clutch plates for holding the opposing teeth in engagement. The opposing teeth of such clutches typically include opposing mating ramp surfaces which are slidable one relative to the other by the exertion of a disengagement force therebetween in opposition to and greater than the spring force, to cause the clutch plates to move away from one another. Such disengagement force can result, for example, from high torque conditions generated as a result of resistance to rotation of a driven one of the rotatable members. If the disengagement force is great enough in magnitude and duration to move the clutch plates out of mating engagement, the teeth of the driving clutch plate can ratchet or move over the teeth of the other clutch plate to allow rotation of the driving clutch plate relative to the other clutch plate. As this ratcheting occurs, there are times when the teeth of the two clutch plates are directly opposing so as to hold the clutch plates apart such that the clutch spring stores a substantial amount of potential energy. Then, as the teeth of the driven clutch plate pass the teeth of the other clutch plate and thus are no longer opposing, the clutch plates are no longer held apart such that the stored potential energy will be partially or fully released to drive the clutch plates together. If this occurs abruptly or suddenly, such as due to fast rotation of the driving clutch plate and/or abrupt stoppage or slow down of driven components, the clutch plates can be rapidly driven together so as to exert a shock force therebetween which can have a magnitude several times that of the spring force and the disengagement force. If the ratcheting continues, the shock force can be exerted numerous times or cyclically so as to have a repeating, hammering effect. The shock force can be transmitted through the clutch components to the rotatable members and other components such as supporting bearings, bushings, drive chains, belts, and the like, and can be damaging thereto. Problems that have resulted include movements of the rotatable members and associated components that result in accelerated wear and breakage. The hammering effect can also loosen connected items such as hardware and the like. Such clutches are often used to transmit relatively large amounts of rotational power, for instance, for rotating feeder apparatus within the feeder house of an agricultural combine, and thus, the spring force and disengagement force can have a magnitude of 1000 pounds or more. The magnitude of resultant shock forces exerted against the clutch plates and associated structure including shafts and the like can be many times that, including up to 10,000 pounds.
Accordingly, what is sought is a shock force damping capability for a jaw clutch which overcomes one or more of the problems set forth above.